I can just see how somebody filled out the entry and due to poor database design, it was allowed in.
Field: RestrictedToAge
Caption: "Restrict Sales to Minimum Age:"
Field Type: Varchar(4) NOT NULL -- WTF, should be NULL-able Unsigned Byte

Answer given of course was "Y", as in Yes, restricted to a minimum age, as opposed to say, 18.

It seems to me like the KM is calculated from the Miles; and that the metres from the ft.

The -2,147,483,648 is the lowest number a signed 32bit integer can represent, which is why it appears as such (obviously). There's obviously a bug in whatever is handling/passing the real data, and instead a 32bit integer's minimum value is being used as a default.

1 Mile is roughly 1.60934 KM, so the calculation would result in a far higher number of (negative) KM. It's just that the data type they're using can't represent it (and seems to not underflow), limiting it to the lowest value it can show - appearing to "not work".

With 1 Mile being 5280ft, the calculation is obviously that there are fewer (negative) miles, which is why it appears to "work" OK.

The Tardis. Of Course! That explains so much. Designing websites for Time Lords would explain the Y age, as Y is sometimes used as 150 in Roman Numerals. And, at 150, your age would be at least three characters long in decimal.

Not sure of the rest, though... maybe the barcode reader started to become sentient?

ASL is a different language from English. Just because you are fluent in one doesn't mean you are fluent in the other. But just because you aren't fluent doesn't mean you can't understand enough to click the link, just like every other language listed there. You see the name of your language and you click, getting the rest from context.

Ah yes, the in-flight displays… also often puzzled by the fact that origin and destination might not be in the same TZ, or in that of the plane, and that planes can move east or west (though if they do both at the same time, good luck).

The conversion function of ft to m is about right although the answer would put the altitude in space past the orbit of the moon on the other side of the planet.
The conversion function of miles to km simply gave up and returned its input, maybe in the spirit of ask a silly question get a silly answer.

Rather than being fractally wrong it looks more like a cascade fail where some wrong data (maybe the location) went through and affected everything that depended on it.
It does highlight the way the later functions work and is more interesting than a simple 'unavailable, please wait' screen that is usually shown to users.